1. Field of the Disclosure
The technology of the disclosure relates to electronic circuit boards that include optical interfaces for converting optical signals into electrical signals and vice versa.
2. Technical Background
Benefits of optical fiber include extremely wide bandwidth and low noise operation. Because of these advantages, optical fiber is increasingly being used for a variety of applications, including but not limited to broadband voice, video, and data transmission. For example, fiber optic networks employing optical fiber are being developed and used to deliver voice, video, and data transmissions to subscribers over both private and public networks.
For example, optical fiber may be employed in data distribution centers or central offices for telecommunications and storage systems applications. These applications include, but are not limited to, server farms, such as for web page accesses, and remote storage equipment, such as for backup storage purposes, as examples. To provide for efficient management of this equipment, data centers include equipment racks, such as the equipment rack 10 illustrated in FIG. 1. The equipment rack 10 in FIG. 1 is comprised of rails 12A, 12B extending in a vertical direction and spaced a distance apart to support a plurality of modular housings 14 disposed between the rails 12A, 12B in vertical space. The modular housings 14 are configured to support information processing devices 16, such as computer servers, data storage devices, and/or other circuits in the form of blades 18, referred to herein as “cards 18.”
The cards 18 are printed circuit board (PCB) cards 18. The PCB cards 18 contain electrical traces interconnecting electrical components mounted on the PCB card 18. If the PCB cards 18 are configured to support optical communications to benefit from the aforementioned advantages of optical fiber, optical interfaces are provided on the PCB cards 18. These optical interfaces can include transmitter optical sub-assemblies (TOSAs) (not shown) to convert electrical signals from the electrical components on the PCB card 18 into optical signals to be transmitted over optical fiber in a fiber optic cable. These optical interfaces can also include receiver optical sub-assemblies (ROSAs) (not shown) to convert received optical signals from optical fiber in a fiber optic cable into electrical signals to be routed over electrical traces in the PCB card 18 to electrical components on the PCB cards 18. The optical fiber of the fiber optic cable is interfaced to the PCB cards 18 through fiber optic connectors mounted on the PCB cards 18. The fiber optic connectors mounted on the PCB cards 18 are optically connected to a TOSA and ROSA through optical fibers mounted on the surface of the PCB card 18 to support optical fiber interfacing between fiber optic cables and the electronic components on the PCB card 18.
Optical fiber interfacing is also being employed in smaller, consumer electronic devices to provide the benefit of enhanced communications performance of optical fiber. Examples of such consumer electronics include, but are not limited to, personal computers, notebook computers, computer tablets, digital cameras, mobile phones, and other mobile devices. These consumer electronic devices also employ circuit boards such as printed circuit boards (PCB(s)) that route electrical signals between electrical components and circuits disposed in the PCB to perform the operations of the electronic devices. Thus, to provide optical communications interfacing these electronic devices just as provided in the data center electronic devices described above, the PCBs can be fitted with fiber optic connectors mounted on the PCB. The fiber optic connections are optically connected to the TOSA and ROSA through optical fibers mounted on the surface of the PCB to support optical fiber interfacing between fiber optic cables and the electronic components on the PCB.